Building a Simple To-Do List App with JavaScript

June 27, 2025

This content originally appeared on DEV Community and was authored by Muhammad Atif Latif

In this post, we’ll create a simple To-Do List application using JavaScript. This app will allow users to add, remove, and mark tasks as complete.

Features of the To-Do List App

Add new tasks
Remove tasks
Mark tasks as complete

Setting Up Your Project

Create a new directory:

   mkdir todo-app
   cd todo-app

Create an index.html file and add the basic structure:

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>To-Do List</title>
    <link rel="stylesheet" href="styles.css">
</head>
<body>
    <div class="container">
        <h1>To-Do List</h1>
        <input type="text" id="taskInput" placeholder="Add a new task...">
        <button id="addTaskButton">Add Task</button>
        <ul id="taskList"></ul>
    </div>
    <script src="script.js"></script>
</body>
</html>

Adding Styles

Create a styles.css file to style your app:

body {
    font-family: Arial, sans-serif;
    background-color: #f4f4f4;
    margin: 0;
    padding: 20px;
}

.container {
    max-width: 600px;
    margin: auto;
    background: white;
    padding: 20px;
    border-radius: 5px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
}

h1 {
    text-align: center;
}

input[type="text"] {
    width: 70%;
    padding: 10px;
    margin-right: 10px;
}

button {
    padding: 10px;
}

ul {
    list-style: none;
    padding: 0;
}

li {
    padding: 10px;
    border-bottom: 1px solid #ccc;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

Adding Functionality with JavaScript

Create a script.js file to add functionality:

document.getElementById('addTaskButton').addEventListener('click', addTask);

function addTask() {
    const taskInput = document.getElementById('taskInput');
    const taskValue = taskInput.value.trim();

    if (taskValue) {
        const taskList = document.getElementById('taskList');
        const li = document.createElement('li');
        li.textContent = taskValue;

        const removeButton = document.createElement('button');
        removeButton.textContent = 'Remove';
        removeButton.onclick = () => {
            taskList.removeChild(li);
        };

        li.appendChild(removeButton);
        taskList.appendChild(li);
        taskInput.value = '';
    }
}

Conclusion

You’ve now built a simple To-Do List app using HTML, CSS, and JavaScript. This project can be expanded further by adding features like task persistence using local storage, editing tasks, or adding a filter for completed tasks.

Feel free to share your thoughts or improvements in the comments below!

This content originally appeared on DEV Community and was authored by Muhammad Atif Latif